Question

Which of the following statement is false regarding Armstrong modulation system?

(a) The system is basically phase modulated and not frequency modulated

(b) Automatic Frequency Control (AFC) is not needed as a crystal oscillator is used

(c) Frequency multiplication must be used

(d) Equalization is necessary

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Question is taken from Noise for AM Wave in section Noise of Analog Communications

Answer 1

The correct option is (d) Equalization is necessary

Explanation: The Armstrong method generates a double sideband carrier signal, phase shifts this signal and then reinserts the carrier to produce a frequency modulated signal. In Armstrong modulation system equalization is not necessary.